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#include <bits/stdc++.h>
#define ll long long
#define debug if (0)

const ll MOD = 1e9 + 7;
const int MAX_N = 2e5;

ll f[MAX_N + 3];
ll f_inv[MAX_N + 3];

int n, m;
std::vector<int> list[MAX_N + 3];
int t[MAX_N + 3];
bool finished[MAX_N + 3];
int color[MAX_N + 3];
bool visited[MAX_N + 3];

ll fast_pow(ll a, int p) {
  if (p == 0)
    return 1;
  if (p % 2 == 0) {
    ll tmp = fast_pow(a, p / 2);
    return tmp * tmp % MOD;
  }
  return a * fast_pow(a, p - 1) % MOD;
}

void precalc_f() {
  f[0] = f_inv[0] = 1;
  for (ll i = 1; i <= n; i++) {
    f[i] = f[i - 1] * i % MOD;
    f_inv[i] = fast_pow(f[i], MOD - 2);
  }
}

ll choose(int n, int k) {
  if (k > n)
    return 0;
  return f[n] * f_inv[k] % MOD * f_inv[n - k] % MOD;
}

bool dfs_color(int v) {
  visited[v] = true;
  for (auto &u : list[v]) {
    if (visited[u] && color[u] == color[v])
      return false;
    if (!visited[u]) {
      color[u] = (color[v] + 1) % 2;
      if (!dfs_color(u))
        return false;
    }
  }
  return true;
}

void dfs_cnt(int v, std::vector<int> &ver) {
  ver.push_back(v);
  visited[v] = true;
  for (auto &u : list[v])
    if (!visited[u])
      dfs_cnt(u, ver);
}

ll solve_cmp(int v) {
  debug std::cout << "!!! solve_cmp(" << v << ")\n";

  std::vector<int> vertices;
  dfs_cnt(v, vertices);
  for (auto &u : vertices)
    visited[u] = false;

  color[v] = 0;

  ll R = 0;
  ll B, C;
  if (dfs_color(v)) {
    // is bipartite
    int N1, N2, K1, K2;
    N1 = N2 = K1 = K2 = 0;
    for (auto &u : vertices) {
      if (color[u] == 0) {
        N1++;
        if (t[u] == 1)
          K1++;
      } else {
        N2++;
        if (t[u] == 1)
          K2++;
      }
    }

    if (K1 > K2) {
      std::swap(K1, K2);
      std::swap(N1, N2);
    }

    int dk = K2 - K1;
    int k2;

    debug {
      std::cout << "It is bipartite:\n";
      std::cout << "N1 = " << N1 << ", K1 = " << K1 << "\n";
      std::cout << "N2 = " << N2 << ", K2 = " << K2 << "\n";
    }
    for (int k1 = 0; k1 <= N1 && k1 + dk <= N2; k1++) {
      k2 = k1 + dk;
      B = choose(N1, k1);
      C = choose(N2, k2);

      debug std::cout << "Adding (" << N1 << " choose " << k1 << ") * (" << N2
                      << " choose " << k2 << ")\n";
      B = B * C % MOD;
      R = (R + B) % MOD;
    }
  } else {
    // is not bipartite
    ll N = vertices.size();
    ll K = 0;
    for (auto &u : vertices)
      if (t[u] == 1)
        K++;

    debug std::cout << "N = " << N << ", K = " << K << "\n";

    // (N choose K) + (N choose K + 2) + ...
    // + (N choose K-2) + ...
    for (int k = K % 2; k <= N; k += 2) {
      debug std::cout << "R += (" << N << " choose " << k
                      << ") = " << choose(N, k) << "\n";
      R = (R + choose(N, k)) % MOD;
    }
  }

  for (auto &u : vertices)
    finished[u] = true;

  debug std::cout << "Returning " << R << "\n";

  return R;
}

void input() {
  std::cin >> n >> m;
  for (int i = 1; i <= n; i++)
    std::cin >> t[i];
  for (int i = 1; i <= m; i++) {
    int x, y;
    std::cin >> x >> y;
    list[x].push_back(y);
    list[y].push_back(x);
  }
}

int main() {
  std::ios_base::sync_with_stdio(0);
  std::cin.tie(NULL);

  input();

  precalc_f();

  ll R = 1;

  for (int v = 1; v <= n; v++)
    if (!finished[v])
      R = R * solve_cmp(v) % MOD;

  std::cout << R << "\n";
}